An international team of researchers led by Keele University have discovered a potential new drug that could be used to reduce infection spread of Covid-19 and other emerging viruses.

Although successful vaccination campaigns have alleviated the Covid-19 pandemic, alternative drug-based interventions are urgently needed because of the potential future risk of variants that are resistant to current vaccines. A special type of cell surface sugars, called heparan sulfates, have recently been found to be critical for binding the SARS-CoV-2 virus – which causes the Covid-19 disease – to cells, opening an attractive new drug target.

The Keele team is the first to demonstrate that an existing drug that mimics heparan sulfate inhibits attachment and infectivity of the SARS-CoV-2 virus. The drug, Pixatimod, is effective against all the key variants of concern that have emerged to date, including Omicron, and is in clinical development as an anti-cancer drug by Zucero Ltd in Brisbane, Australia.

The virus infects cells using a "spike protein" on its surface, which binds with a receptor site on the cell. The findings, published in ACS Central Science, showed that Pixatimod blocks the binding of the virus to the cell surface, by interacting with the tip of the spike protein, where it normally sticks to a protein receptor called ACE2.

This work shows for the first time that drugs which mimic heparan sulfates are promising as anti-viral agents against SARS-CoV-2 variants. This opens the way for clinical investigations to repurpose Pixatimod against SARS-CoV2 and other emerging viruses, potentially as a nasal spray to reduce infection spread.

Professor Jerry Turnbull, who led the research, said: "We also know that Pixatimod inhibits other viruses, so studying these drugs could provide totally new therapeutic strategies, and possibly a first-line of defence against emerging viral threats in the future, including vaccine escape variants of SARS-CoV2. This could include application as a prophylactic treatment for high-risk groups such as medical staff or care workers."

The work was led by Professor Turnbull, with Dr Scott Guimond, Dr Mark Skidmore, and Dr Marcelo Lima, from the Centre for Glycosciences and School of Life Sciences at Keele, and also involved an international consortium of researchers from University of Liverpool, Oxford University, Public Health England, University of Southampton, Copenhagen, Gothenburg and Australia.